The purpose of this clinical research study is to learn if BMS-232632 administered as Atazanavir/ritonavir (ATV/RTV) is superior to an anti-retroviral regimen including Lopinavir/ritonavir (LPV/RTV), as assessed by an increased brachial artery flow-mediated vasodilatation (FMD), in HIV-infected patients. The safety of this treatment will also be studied.